In a supermarket or department store, the purchased commodities are registered and settled using a commodity sales data processing apparatus, such as a POS (Point of Sales) terminal or a register, which comprises an optical reader. To register a commodity using the commodity sales data processing apparatus, the optical reader is used to read a commodity code such as a barcode or a two-dimensional code attached to the commodity, and the commodity sales data processing apparatus executes a commodity registration based on the read commodity code. The commodity sales data processing apparatus prints commodity information or settlement information serving as a result of the commodity registration on a receipt paper and then issues the receipt. The customer takes the issued receipt to keep an account of household expense with the receipt information such as the commodity information or the checkout information printed on the receipt.
However, with the popularization of a portable terminal such as a mobile phone, a smart phone or a tablet PC, customers hope to use a portable terminal to receive and display settlement information.